Printers for printing desired information such as text and images on sheet-like print media such as paper and film are used widely as information output devices in word processors, personal computers and facsimile machines, by way of example.
The ever wider use of printers is accompanied by an increase in the types of print media (paper) employed in printing. For example, various print media such as plain paper, high-quality paper, labels, coated paper and photo paper are used in printing.
In the prior art, the setting of the print medium to be used in printing generally is performed by the user via a printer driver. In recent years, however, printers equipped with a media sensor for sensing the type of print media used have been proposed with a view to mitigating the load to which the user is subjected (for example, see the specification of Japanese Patent Application Laid-Open No. 10-198093).
Further, with a printer equipped with a media sensor, the type of print medium is detected at a prescribed timing when the medium is fed, print data is generated based upon the result of detection and printing is executed (for example, see the specification of Japanese Patent Application Laid-Open No. 2003-136813).
Assume that printing is performed by a printer having a plurality of paper feed means [an automatic sheet feeder (ASF), paper feed cassette or photo deck, etc.] capable of being switched by the user, and that a media sensor is provided for just one of these feed means. Depending upon the relationship between the timing at which the user switches the feed means and the timing at which media sensing is performed, media sensing may be carried out for detecting the type of print medium stacked in feed means that is not actually used in printing, and the result may be the generation of print data based upon erroneous information.
In such case print data that conforms to the print medium used will not be generated and the printing that is intended will not be executed. As a consequence, not only is the print medium and printing agent such as ink and toner wasted but it is also possible that soiling or malfunction of the apparatus will result.